Cut the Fat

I was headed to the DMV to renew my driver's license, and I had to walk past a food court to get there. Even though I had just eaten lunch, the smell of pizza and Chinese food was making my stomach rumble, and I could practically feel my pupils turning into tiny cheeseburgers, cartoon-style. Ninety minutes' worth of paperwork later, I was slathering extra frosting on a Cinnabon. "We're continually being offered calorie-dense food in big portions, and we don't have to work hard or spend much money to get it," says Barbara Rolls, PhD, the author of The Ultimate Volumetrics Diet. "If you wanted to fatten someone up, you couldn't design a much better environment than the one we live in." And a lot of Americans are succumbing: 33 percent of adults are overweight and 36 percent are obese. But there's good news: You can beat the odds and ditch extra pounds. Here, the 10 hurdles standing between you and your goal weight — and how to tackle every one.

Food Is Everywhere All the Time

Turn on the TV, fire up your laptop, or open a magazine, and there it is: food porn. Nearly 60 percent of the Pinterest content that we interact with is culinary, more and more non-grocery stores are selling food (think a hot dog stand at the hardware store and mini pizzas at Target), and there were 32 percent more food ads on television in 2011 than in 2007. The average person now watches 20 mouthwatering commercials a day, according to Yale University research.

The problem is that "seeing or smelling food activates pre-eating responses, like salivating," Rolls says. But just as spotting a doughnut can trip your splurge trigger, leaving your running log out on the coffee table can activate your stay healthy one. Research shows that overweight grocery shoppers who were handed a recipe with health-related words printed on it bought less junk food than those who got otherwise identical recipe cards. "It didn't matter whether participants thought about or looked at the card again," says study author Esther Papies, PhD, an assistant professor at Utrecht University in the Netherlands. "These reminders work subtly." To give your brain the hint, hang your bathing suit from your bedroom doorknob or put the class card for your favorite yoga studio in the front part of your wallet.

There's Too Much Variety

Take a buffet: If you have just a few bites of each dish, you'll still consume far more calories than you would if there were only two or three foods on your plate. Even when you're not in an all-you-can-eat situation, having too many choices can sabotage your diet. That's because when you devote mental energy to reviewing all of them, your brain gets overwhelmed and your willpower suffers.

"People in other countries tend to have the same thing for breakfast and lunch every day," says Brian Wansink, PhD, the director of the Food and Brand Lab at Cornell University and a FITNESS advisory board member. "Here, there's no pattern at all. One day you skip breakfast, the next morning you have leftover pizza, and the next morning you buy a caramel latte. All this food freedom leads to taking in more calories."

Wansink suggests eating more or less the same balanced breakfast and lunch every weekday, changing up dinner so you don't get bored. Claire Wheeler, MD, PhD, a professor of community health at Portland State University and a coauthor of The Complete Idiot's Guide to Belly Fat Weight Loss, takes this approach: "I stick to the same few proteins and grains, but I switch up my fruits and vegetables," she says. "Variety in that aspect is good, because different kinds of produce contain different nutrients."

Fat and Sugar Are Hijacking Our Brain...

Junk food has more fat, sugar, and salt than ever before, and all three can affect the brain in the same way drugs and alcohol do. "Food scientists know exactly how to make the french fries in a restaurant more addictive than anything you could make at home," Dr. Wheeler says. Namely, they engineer them to light up the pleasure center in your brain while throwing off your body's "I'm full" signals, so it's hard to feel satisfied no matter how many you have.

But don't quit eating your faves cold turkey. "If you try to cut something out completely, you're likely to go overboard if you do cave, because you think, This is my last chance to eat this, so I had better make it count and go all out," says Deborah Beck Busis, the diet program coordinator for the Beck Institute for Cognitive Behavior Therapy in Bala Cynwyd, Pennsylvania. "Instead, allow yourself a small serving and get used to the feeling of stopping once it's gone." Another trick: Indulge in activities you enjoy, like Spinning or playing Words With Friends, Dr. Wheeler suggests. They have the same pleasure-producing effect on brain chemistry as hyperpalatable foods, minus the calories.

...and Our Gut

We all have a mix of good bacteria, which help us break down food and fight off sickness, and bad bacteria, which can muck up digestion, metabolism, and immunity. The newest research hints that a diet high in fat and low in fiber can cause a proliferation of bad bugs, which tell your digestive tract to store more calories as fat. (Good microbes tell your digestive system to let more calories through unabsorbed.) "This means that if two women eat the same 100-calorie candy bar, the one with a healthier mix of bacteria might absorb just 80 calories, while the other might absorb all 100," Dr. Wheeler explains.

To slow the absorption of calories, aim to get 25 grams of fiber a day. "The nutrient increases the production of mucus in the gut, and good bacteria need mucus to survive," says David Rakel, MD, an associate professor of integrative medicine at the University of Wisconsin-Madison.

We're Lame in the Sack

"Since the recession, we feel that we need to be working at all hours to prove our worth," Dr. Wheeler says. And once we do go to bed, high levels of the stress hormone cortisol prevent us from slipping into dreamland.

The problem is that not logging enough zzz's doesn't just make you drowsy during the day, it can also increase levels of the hunger hormone ghrelin, reduce levels of the satiety hormone leptin, and give more clout to genes — including the bad kind that tell your body to gain weight the second you stray from your diet or take a break from the gym. "The more people sleep, the less sway their genes have over their weight, and the more diet and exercise matter," says Nate Watson, MD, the codirector of the University of Washington Medicine Sleep Center in Seattle.

To get your seven or more hours, skip caffeine in the evening, power down your electronics at least an hour before bedtime, go to sleep and get up at about the same time every day, and make sure your bedroom is pitch-black.

Our Social Circle Is Growing, and Not in a Good Way

After tracking more than 12,000 health care professionals for 32 years, Harvard Medical School researchers found that their subjects' obesity risk was 57 percent greater if they had a close friend who was obese, 40 percent greater if a sibling of theirs was obese, and 37 percent greater if their spouse was obese. One explanation: The researchers suspect that unhealthy activities are contagious (if your BFF loves going out for happy hour nachos, you'll probably partake, too). Also, if the majority of the people in your life are packing extra pounds, being overweight can begin to seem like the norm.

Fight weight creep by finding ways to turn social time into slimming time. "People are willing to change, but you have to take the lead," Busis says. Suggest meeting at a healthy soup-and-salad cafe instead of a Chinese buffet or taking a kickboxing class together instead of seeing a movie.

We Love a Bargain

You probably shop at least occasionally in one of the more than 4,000 big-box stores in the U.S., like Sam's Club and Costco. And once you get your purchases home, they can cause something called stock pressure, Wansink says. "You open the cupboard and think, Whoa, look at all those chips!" Suddenly, you're worried about polishing them off before they go stale or just clearing some room on your shelves.

If you must buy an economy-size bag of chips, crackers, or cookies, repackage it in smaller baggies as soon as you get home, Wansink suggests. Or put bad-for-you bites in the very back of your cabinets, where you're less likely to see them.

Portion Sizes Keep Climbing

A report in the International Journal of Obesity examined 52 well-known paintings of Jesus' last supper, comparing portions and dishware. The results: Since 1000 A.D., the size of entrees has grown by 69 percent, bread by 23 percent, and plates by 66 percent.

If you aren't already eating dinner off salad-size plates, make the switch. Then dish out 20 percent less food than you think you need: Cornell researchers found that a 20 percent reduction didn't make people feel any less full. At restaurants, ask the server to box up your leftovers. And if you chose something that won't hold up well the next day, "get over the idea of getting your money's worth," Busis says. "You're paying the same amount whether you finish your food or not. And when you think about the cost of taking in too many calories, it's just not worth it."

Health Halos Are Blinding Us

Buying the light version of packaged foods instead of the regular kind could make you heavier. When people were served treats that had a "low fat" sticker on the package, they ate up to 47 percent more than those who were served the same snacks minus the label, a Cornell study showed. In fact, just seeing the phrase "low fat" caused people to consume an extra 89 calories in a sitting. "People think they're being good, so they compensate by eating more," Wansink says. Other health claims — "gluten-free," "all natural" — also spur us to justify eating more. "But these foods aren't necessarily healthier," he says.

Weirdly, knowing about the halo effect doesn't make us any less susceptible to it, Wansink notes. So whether you're reaching for rice cakes or Oreos, count out a single serving, then close up the box or bag. "Every time you stick to a reasonable portion instead of overeating, your resistance muscle gets a little stronger and your giving-in one gets a little weaker," Busis says.

We Pay for Everything with Plastic

Studies show that we're likelier to splurge on an expensive bag or gadget when we use a credit card, because swiping doesn't feel like spending money. Now a study in the Journal of Consumer Research shows that we also buy less-healthy fare when we pay with credit instead of cash, because our brains trick us into thinking that if it doesn't count financially, it doesn't count caloriewise either.

Busis recommends taking out enough money each Monday for seven days' worth of food. "Doing this can help you become more aware of how you're spending your grocery dollars," she says. And use the cash trick when eating out, too. "If you've budgeted $20 to spend on dinner, you may have to get an appetizer instead of an entree or stick with water instead of ordering wine," Dr. Wheeler says. "When you're more mindful of how much you're spending, you're also more mindful of how much you're eating."